Remesh will distort the existing UVs. It tries not to, but inherently the operations it does to refine the mesh will result in some shifting of the UVs relative to the surface. It can be subtle but it’s not a “bug” in the sense of a mistake that we can fix, it’s more like a mathematical property of the remeshing strategy, it wants to slide the vertices “sideways” on the surface, while their UVs stay stationary, which introduces distortion. We try to constrain the vertex movement so that the UVs won’t become distorted but it sometimes is not possible.
If you want to post your mesh I can have a closer look but I would guess that this is where the distortion is coming from.